Mechanically-operated lead pencil



D. M. BALLOU MECHANICALLY OP Jan. 5l 1926.

ERATED LEAD PENCIL Filed July 14, 1925 l I lllilldx Patented Jan. 5, 1926.

UNITED STATES g 1,568,951 PATENT OFFICE.-

DAYID M. IBALLO'U, OF MANSFIELD, MASSACHIISETTS, ASSIGNOIt TO REX MANUFAC- TUBING C0., OF PROVIDENCE, RHODE ISLAND, A CORPORATION OF RHODE ISLAND.

MECHANICALLY-OPERATED LEAD PENCIL.

To all whom t may comer/n.'

Be it known that I, DAVID M. BALLOUL, a citizen of the United States, residing at Mansfield, in the county of Bristol and State of Massachusetts, have invented certain new and useful Improvements in Mechanically-Operated Lead Pencils, of which the following is a specification.

This invention relates to an improved construction of mechanically-operated lead pencil, and has for its object to provide an improvement in the construction of such a pencil having means for permitting a continued rotation of `the parts even after the lead-carrier has been either advanced or retracted to the end or limit of its movement, without straining or rupturing the parts of the pen'cil.

A further object of the invention is to construct' the worm member of the pencil and the driving end portion of the pencil in two separate parts and connect them together thereby permitting these parts to operate smoothly even though they are not in perfect axial alignment one with the other.

A still further object of the invention is the provision of a sprin working end of the pencil against which the operating end of the worm receives a cushioning thrust, which performsa number of useful functions; among others being that the yieldability of the spring permits' a softer or smoother actionI of the rotating parts of the pencil and permits of an axial movement of the worm to allow the worm to become disengaged Tfrom the manual driving element after the carrier has reached the end of its stroke to revent rupture of the parts; also permlts the "carrier to be forced outwardly beyond the end .of the worm in its extreme advanced position to permit the worm to snap by lthe worm-engaging portion of the 'carrier and toprovide yielding means for permitting a continued rotation of said member in the same direction after the carrier has reached the end of its feeding stroke. f,

With these and other objects in view, the invention consistsvof certainnovel features of construction, as will be more fully described, and particularly pointed out in the ap ended claims.

n the accompanying. drawings:

Figure 1`is an enlarged sectional side elevation of my improved construction of pen located at thel Application led J'uly 14, 1925. Serial No. 43,589.

cil showing the carrier and ejector nearr the top of their retracting strokes and the driving clutch members in engagement.

Figure 2 is a fragmental portion artially 1n section showing the carrier andJ ejector members at the bottom of their strokes and the worm as forcing theengaging portions of these members downwardly against the pressure ofthe spring.

Figure 3 is the same as Figure 2 but showing the engaging portions of the carrier and ejector -as having snapped upwardly into position to be engaged progressively by a revgersing or retracting action of the worm.

j Figure 4 is a sectional view of a portion of the pencil showingthe driving clutch members in partiallydisengaged position, the worm having moved axially downwardly against the pressure of the spring.

Figure 5. shows the clutch members as being entirely disengaged, the worm member having moved further downwardly to fur ther compress the spring.

Figure 6 is a section on line 66 of Figure 1 with the barrel portion removedl showing the engaging portlons of the clutch block and the worm.

Figure 7 is a perspective view of the ejector pin.

Figure 8 is a perspective view of the lead carrier.

Figure 9 is a lperspective view of the slotted guide tube.

Figure 10 is a sectional side elevation of the collar and showin the inturned finger ortionon the collar 1n position to serve as a ey to slide in the slot of the guide tube.

It is found in the practical construction and operation of mechanically-operated pencils' of this character, of advantage to -reached the upper end of their operating strokes so as to prevent rupture of these parts. It is also found of advantage to provide means at the lower end of the worm whereby when the ejector and the carrier have reached the end of their ejecting stroke by action of the worm, a further expelling action of the worm will force these members downwardly to compress the spring and so permit the worm to receive a continued expelling rotation without injury to the parts; also this spring serves to immediatel reposition the engaging cud of the ejector member so that a reverse rotation of the screw causes it to first pick up this ejector and the friction of its retracting movement serves to also lift the carrier so Y, that the next revolution of the worm engages and lifts this carrier and both receive their proper retracting action. An additional function of this spring is to provide a smooth yielding pressure against the end of the worm, whichholds the parts in yielding engagement with-each other and provides a smooth and flexible turning action to the parts during the feed and retracting rotation of the pencil members; and the following is a' detailed description ofthe present embodiment of my invention and showing one means by which these advantageous results may be accomplished With reference to the drawings, 10 designates the barrel or body portion of a pencil, which may be made of any suitable material, but which is preferably made of rubber composition tubing and may be made in a variety of different colors. These tubes are cut to the desired length and each is preferably internally threaded as at 11 adjacent the pointed end thereof, into which is screwed a corresponding threaded hub 12 of the sleeve oint bushing 13, which bushing is tapere on itsl outer surface to receive a separate conically-shaped pointed sleeve 14.- The inner or central portion of this bushing, is provided with a bore 15 nearly its entire length, of a size to receive a coiled spring 16, the lower end of which rests against a shoulder 17 of the bore. The lower end of this bushing is threaded internally at 18 for the reception of the threaded end 19 of the separate point end member 20. The worm member 21 receives a bearing at its lower end 22 in the upper end of the bore 15. This end of the worm is arranged to rest upon the collar 23 which is supported on the upper end of the spring 16.

Mounted in this worm is the guide tube 24 which is partially closed at its upper eiid by inturned stop fingers 25. This guide tube is slotted internally as at 26.

In this tube is mounted a tubular leadcarrier having a laterallyextending linger portion 28 projectin into a. groove 29 ofthe worm, its lower en 30 being arranged to receive and grip the inner end 32 of the lead 31.

Within the carrier is slidably mounted an ejector 33 which is offset at its upper end as at 34 to extend into the groove 29 of the worm whereby a rotation of the worm causes both the ejector and the carrier to move endways along the pencil. This sleeve or collar 23 is provided with an inturned finger 35 which projects into a slot 26 of the guide tubing and this inturned linger is cut lfrom the stock of the collar and provides a recess 36 into which the worm-engaging end 28 of the carrier may be forced, as presently described.

Into the upper end of the tube 10 of the pencil, I have threaded a plug 37 and through this plug I extend a long sleeve 38 to the upper end of which is fixed a rotating portion 39 of the encil and to the lower end is fixed the clutc block 40, the same having an inclined abutting face 41 to engage a correspondingly inclined abutting face 42 of the worm end, whereby rotation of the operating member 49 in one direction imparts a retracting motion to the ejector and the. carrier until the ejector end 34 brin up against the stop 25 in the guide tube when a continued rotation in the same direction causes these inclined surfaces 41 and 42 to force the worm downwardly against pressure of the spring 16, permitting the clutch members to separate and ride one upon the other, thus permitting this continued rotation without rupture of the parts which is of considerable advantage owing to the fact that if too much strain were placed on the old construction which did not yield at the end 'of the stroke, breaka e of the parts would occur and the pencil estroyed.

\ When it is desired to advance the lead into position beyond the point of the pencil, to be used, the operating member 39 is rotated in an opposite direction and both the ejector and the carrier are advanced until the lead projects the desired amount beyond the point of the pencil.

In some instances, after the lead has been broken off or otherwise become too short and to prevent rupture of the parts by continued rotation of the driving head after the ejector and carrier have been propelled to the extent of their feeding stroke, I cause the worm to advance the worm-engaging end 28 of the carrier into'the slot 36 of the collar 23 and the next revolution of this worm in the same direction advances the end 34 of the ejector to lie in engagement with the upper edge of the collar and a further rotation of the worm in the same direction causes the spring to be compressed and the worm to ride over the end 34 of the ejector into the position best illustrated in Figure 2, and at each rotation of the worm in this direction this end snaps up into engagement with the surface 43 of the worm thus permitting free rotation of the worm in this .direction without injuring any of i the parts of the the same should .y but I Vdesire it to vnism no harm can erator that the -rier serving to raise the carrier so that its end 28 will be lifted above the'slot. 36 inthev collar and in position to be engaged by the point 44 of the `worm whereby both will proceed to be raised in their krelative positions by continued rotation of the'vworniin this retracting direction. j 4

My improved pencil is very simple and practicalato construct, is ei'ective'in its op` eration and by the use of my clutch mechacome to the pencil when the carrier and ejector itis rotated, after endof their strokes in have reached .tlie` either direct-ion. n

The 'foregoing description is 'directed solely towards'the construction illustrated,

be understood that I reserve the privilege o f resorting to' all the fmechanical changes to which the device *is barrel, a lead carrier,

`said carrier to advanced or'retracted posisusceptible, the invention being defined and limited only by the terms of the appended claims. y

I claim: 1. In a mechanically-operated pencil, a lead carrier, an Lejector, va rotatable worm member for feeding both said 4carrier and ejector, a collar notched to receive the worm engaging portion 'of said carrier when vexpelled from the worm, a spring for pressing the collar to ride against the end of the,y

worm and' ada ted `to yield and permit said collar `to recede and .so Apermit both said carrier and ejector to be yieldingly pressed beyond-the end of theworin to carrier and ejector have. reached the end of their feeding strokes. f I j '2. In "a`mechanically-operated pencil, a

Y lead ejector, alead carrier, a slotted ,guide tube in which said ejector v and carrier are mounted, a rotatable worm member surrounding said guide tube,

a portion guided in said tube slot and notched to receivethe worm-engaging o`rom..

tion. of said `carrier when expelled the groovein the worm, a spring acting on said 'collar to permit it? to recede upon being expelled with said ejector by said worm to permit a continued rotation .of the worm. in the saine direction without rupture ofe feed the earner, andmeans for permitting the parts. e p 3. In a 'mechanically-operated pencil, a a worm for feeding tion, a manually rotatable element, inter- 'engaging z frictional means between said I permit the ,worm to continue .its rotation .after both the a collar having lead carrier,

worm and element for rotating said worm 4in either direction, and means for permitting the driving action of said frictional means t'o become ineffective upon a continued retractive-movement when the carrier has reached the end ofits stroke. 1

4. In a mechanically-operated pfencilya-j barrel, a lead carrier,.a worm for. feeding said carrier to advanced or retracted position, la manually rotatable element, interengaging driving connections Abetween said worm and" element, yielding means for 'i holding the same in engagement but pering al notched end, a manually rotatable clutch, for engaging saidnotched end to. y

have a'rotative driving'connectioma spring for normally pressing said clutch and worm Vrinto operative engagement, said worm having an axial movement relative to` said.

clutch against the action of said spring to disengage the `driving connectionv uponl a manual rotationof the clutch after the carrier has reached' the limit of-its retracted position.

6. In .a mechanically-operated pencil, a

lead carrier, a worml for .feeding said carrier to advanced or retracted Vposition and having an inclined abutment, a manually rotatable clutch element having a similarly jinclined abutment for engagement therewith retracted position, aspring for' pressing said abutments into driving engagement, the I inclination of said abutments causing the same tohave a relative axial movement to disengage the driving connection therebeqtween upon a resistance being' offered to the turning ofsaid worm by said manually oper- 'able clutch.

'7. In a mechanically-operated. pencil, a

barrel, afslotted guide tube fixed relatively thereto, an endways movable lead carrier in said `tube,vmanually operable driving means; a propelling .worm for said carrier about vto rotate the worm and-feed said carrier to l I said tubefmounted to receive a, rotative movementv from said manually driven means, and an axial movement relative to said tube to be` disengaged from. the rotative action of said manual means.

8. In a mechanically-operated pencil, a

lead carrier,

an operating worm therefor, a

driving member for .rotating'said worm to.

said worm to receive an axial movement'to 1 be disengaged from its driver when the carrier has reached the end of its stroke. j

9; In a mechanically-operated pencil, a

an .operating worm therefor, a

ydriving member, a clutch connecting said member with said Worm through which the worm may be rotated to feed the carrier, and yielding means whereby said Worm and member may receive a relative endways movement for automatically disengaging said driving clutch when the carrier has reached the end of its stroke.l

10. In a mechanically-operated pencil, a

10 lead carrier, a worm, amanually rotatable member for operating said Worm, said worm being mounted to also receive an axial movement relative to said member to permit the same to be rotated without rotating said Worm after. the carrier has reached the end of its stroke.

In testimony whereof I aiix my signature.

DAVID M. BALLOU. 

